Coverplates for Centrifugal Pumps

ABSTRACT

Embodiments of the invention extend the viability of centrifugal pumps commonly used by fracturing blenders by utilizing, for example, a coverplate with an integrated flange. The coverplate is adapted to be attached to the pump and piping of the fracturing blender. The coverplate can include a substantially cylindrical body of a first and second sides having an outer surface with a circumferential outer rim that substantially surrounds the outer surface. The substantially cylindrical body can also surrounding an orifice. The first side of the coverplate side includes, for example, a substantially circular face that at least partially tapers, the second side includes the integral flange with a circumferential groove and extends outwardly away from the first side. Embodiments of the invention also include methods of attaching the coverplate to the pump and the pipe and operating the pump with the coverplate attached thereto.

RELATED APPLICATIONS

This application claims priority to and the benefit of U.S. Provisional Application No. 61/919,274, titled “Coverplates for Centrifugal Pumps” and filed on Dec. 20, 2013, the contents of which are incorporated herein by reference in its entirety. This application is also related to U.S. patent application Ser. No. 14/578,367, titled “Double Mechanical Seal for Centrifugal Pump” and filed on Dec. 20, 2014, which claims priority to U.S. Provisional Application No. 61/919,353, the contents both of which are incorporated herein by reference in their entireties.

BACKGROUND OF THE INVENTION

1. Field of the Invention

Embodiments of the invention relate to centrifugal pumps, and in particular to centrifugal pumps used with fracturing blenders.

2. Description of the Related Art

Centrifugal pumps such as but not limited to National Oilwell Varco's Magnum XL and XP pumps and Mission's Magnum XP pumps are commonly used on fracturing blenders to pump materials that are used in hydraulic fracturing. These pumps typically pump materials that include sand and other abrasive or corrosive materials. Conventional assemblies connecting the suction piping to the pump include, for example, a suction flange, gasket, and a separate spool piece that is between the gasket and a suction cover.

Inventors of the present invention recognize that one or more of the foregoing may cause the premature failure of the suction flange or suction cover, leaks in the piping, or erosion of the impeller from the pre-rotating fluid. Embodiments of the invention are directed to addressing one or more of the foregoing problems.

SUMMARY OF THE INVENTION

Embodiments of the invention extend the viability of centrifugal pumps commonly used by fracturing blenders, for example. Embodiments include, for example, a coverplate adapted to be attached to a centrifugal pump and piping of the fracturing blender. The coverplate can include a substantially cylindrical body of a first and second sides having an outer surface with a circumferential outer rim that substantially surrounds the outer surface. The substantially cylindrical body can also surrounding an orifice with an at least partially tapered diameter that decreases from the first side to the second side. The first side of the coverplate includes, for example, a substantially circular face that at least partially tapers toward the second side (e.g., the center of the coverplate) and adapted to be positioned at least partially within a centrifugal pump when the coverplate is attached to the centrifugal pump. The second side of the coverplate can include an integral flange extending outwardly therefrom away from the first side and the pump when the coverplate is attached to the pump. The flange of the second side circumscribed by a circumferential groove adapted to facilitate attachment of the coverplate to a suction pipe using a clamp coupling. The outer rim of the first and second sides having a plurality of apertures adapted to receive connecting members to facilitate the coverplate attaching to the centrifugal pump.

Embodiments of the invention include methods of attaching the coverplate to a pump and operating the pump with the coverplate attached thereto. The method comprising, for example, the steps of positioning the coverplate such that at least part of a first side of the coverplate is positioned within a centrifugal pump, the first side of the coverplate having a substantially circular face that at least partially tapers, and attaching the coverplate to the centrifugal pump using one or more connection members. The method embodiments can further comprise the steps of mounting the centrifugal pump to a fracturing truck and attaching piping of the fracturing blender to the second side of the coverplate. Method embodiments can also include, for example, operating the pump with the coverplate attached thereto, the coverplate having a substantially cylindrical body surrounding an orifice with an at least partially tapered diameter, and an integral flange. Pumped materials pumped by the pump flowing from the piping, though the orifice of the coverplate and to the pump intake of the pump.

BRIEF DESCRIPTION OF THE DRAWINGS

So that the manner in which the features and advantages of embodiments of the invention, as well as others, which will become apparent, may be understood in more detail, a more particular description of embodiments of the invention briefly summarized above may be had by reference to the embodiments thereof, which are illustrated in the appended drawings form a part of this specification. It is to be noted, however, that the drawings illustrate only various embodiments of the invention and are therefore not to be considered limiting of the inventions' scope, which may include other effective embodiments as well.

FIG. 1 is a side cross sectional view of the coverplate according to an embodiment of the invention.

FIG. 2 is an enlarged cross-sectional side view of the portion of the coverplate of FIG. 1 indicated by area 2, including a circumferential groove of the coverplate.

FIG. 3 is an isometric view of a first side of the coverplate of FIG. 1, according to an embodiment of the invention.

FIG. 4 is an isometric view of the coverplate attached to a centrifugal pump according to an embodiment of the invention.

DETAILED DESCRIPTION OF THE INVENTION

So that the manner in which the features and advantages of the embodiments of the present invention, which will become apparent, may be understood in more detail, a more particular description of the embodiments of the present invention briefly summarized above may be had by reference to the embodiments thereof, which are illustrated in the appended drawings, which form a part of this specification. It is to be noted, however, that the drawings illustrate only various embodiments of the present invention and are therefore not to be considered limiting of the present invention's scope as it may include other effective embodiments as well.

Embodiments of the invention extend the viability of centrifugal pumps commonly used by fracturing blenders by utilizing, for example, a coverplate 10 with an integrated flange 402. Conventional assemblies connecting the suction piping to the pump include, for example, a separate suction flange, gasket, and a separate spool piece that is between the gasket and a suction cover. The inside diameter of conventional suction piping is approximately 12.5 inches and the inside diameter of the suction flange on conventional assemblies on the pump entrance is approximately 13.5 inches. The inventors recognize that when materials are pumped through this space, this sudden enlargement in piping causes one or more eddy currents that are rotating counter to the flow coming into the pump which causes a concentration of sand to mill at the weld joint area and gasket joint areas. The erosion is further compounded, the inventors recognize, by the lack of laminar flow entering the impeller. Moreover, the pre-rotating fluid moves the eddy currents in a circular motion with the pump's rotation, which results in erosion of the suction flange outward across the gasket surface and the flange welds. Inventors of the present invention recognize that one or more of the foregoing may cause the premature failure of the suction flange or suction cover, leaks in the piping, or erosion of the impeller from the pre-rotating fluid. Embodiments of the invention are directed at addressing one or more of the foregoing problems thereby extending the viability of the pump.

Embodiments of the coverplate 10 can be attached to centrifugal pumps 400 such as, but not limited to, National Oilwell Varco's Magnum XL and XP pumps and Mission's Magnum XP pumps. The pump 400 can be mounted on a fracturing truck to pump material that are used in hydraulic fracturing. Embodiments of the coverplate can also be attached to a pump mounted to a trailer mounted fracturing blender or a skid mounted fracturing blender. Because of the abrasive materials that are pumped in hydraulic fracturing, the coverplate is cast from a material that is suitable for the application of abrasive and erosive materials. According to an embodiment of the invention, the coverplate 10 is cast from substantially the same material as the pump 10 such as, for example, high chrome alloy. According to some embodiments, the integrated flange 402 is long enough to facilitate a fourteen inch (14″) clamped coupling, such as a clamped coupling made by Victaulic®, to the fracturing blender's 14″ inches, schedule 80 pound piping. Advantageously, embodiments of the invention eliminate the need for the separate spool piece that is between the flange gasket and suction cover in conventional arrangements.

FIG. 1 illustrates a cross-section of the coverplate 10 according to an embodiment of the invention. The coverplate 10 includes, for example, a substantially cylindrical body 128 having an outer surface with a circumferential outer rim 210. The substantially cylindrical body 128 surrounds an orifice 122 that extends from a first side 100 of the coverplate to a second side 200 and vice versa. As illustrated in FIG. 1, according to an exemplary embodiment of the invention, the orifice 122 has a tapered inner surface 120 that decreases from the first side 100 to the second side 200. For example, an inside diameter 104 of the orifice 122 at the first side can be approximately 13.386 inches, and an inside diameter 124 of the orifice at the second side can be approximately 12.500 inches according to an embodiment of the invention. According to an exemplary embodiment, the inside diameter 124 of the orifice at the second side is approximately the same as the inside diameter of the piping. The smooth and gradual taper 120 of the orifice 122 (and integral flange) enables a gradual taper into the suction entrance of the pump when the coverplate is attached to the pump. This provides a smooth and gradual curvature to promote laminar flow, so that there are fewer to no areas where solids such as sand can be trapped out of the pump's flow and mill holes into the internal components. Embodiments of the present invention reduce the occurrence of eddy currents and improves laminar flow through the pump entrance, which in turn reduces the occurrence of erosion damage and extends the life and dependability of the pump.

The first side 100 of the coverplate 10 is adapted to attach to the centrifugal pump 400, and the second side 200 is adapted to attach to piping of a fracturing blender trailer using a clamp coupling. FIG. 3 illustrates an embodiment of the first side 100 of the coverplate 10 according to an embodiment of the invention. As illustrated in FIG. 3, the first side 100 can have a substantially circular face 208 that at least partially tapers towards the second side (e.g., tapers towards the center of the coverplate). In FIG. 1, a cross section of the tapered face 208 is shown, including the taper 114.

The substantially circular face 208 of the first side 100 is adapted to be positioned at least partially within the centrifugal pump 400 when the coverplate is attached to the centrifugal pump 400. The outer rim 210 that substantially surrounds the substantially circular face 208 can include a plurality of apertures 202 through the first 100 and second 200 sides adapted to receive connecting members 204 (shown in FIG. 4) when the coverplate 100 is attached to the centrifugal pump 400. According to certain embodiments, a gasket may be positioned between the first side 100 of the coverplate 100 and the pump to facilitate attaching the coverplate to the pump. In this configuration, the coverplate 100 and the pump 450 may not be directly engaged, and are nevertheless still attached to one another, albeit with the gasket in between. Embodiments of the invention eliminate the need for a separate spool piece that is between the flange gasket and the suction cover currently used in conventional assemblies.

According to an embodiment of the invention, an outer edge of the substantially circular face 208 can have a diameter 106, and the substantially circular face 208 can be circumscribed by a step 118. The diameter 108 of the coverplate 10 on the opposite side of the step 118 from the substantially circular face 208 can be slightly larger than the diameter 106 of the outer edge of the substantially circular face 208. In the embodiment shown in FIG. 1, for example, the diameter 106 can be about 22.094 inches, while the diameter 108 can be about 23.122, although any appropriate dimensions can be used depending on the size of the pump and other considerations. This step 118, according to an embodiment of the invention, engages with one or more surfaces of the pump to facilitate attaching the coverplate to the pump. The substantially circular face 208 is positioned, for example, adjacent to the impeller 406 of the pump when the coverplate is attached to the pump and the outer rim 210 of the first side is attached to the outer surfaces of the pump using one or more connection members 204.

FIG. 4 illustrates the coverplate 100 attached to a centrifugal pump 400 according to an embodiment of the invention. FIG. 4 also illustrates the second side 200 of the coverplate according to an embodiment of the invention. The second side 200 can include, for example, an integral flange 402 extending outwardly away from the first side 100 and facing outwardly from the pump 400 when the coverplate is attached to the pump 400. The flange 402 is circumscribed by a circumferential groove 112 that is adapted to facilitate attachment of the coverplate to the piping using a clamp coupling so that the pipe can be positioned substantially perpendicular to the impeller 406 of the pump. FIG. 2 illustrates a close up of the circumferential groove 112 according to an embodiment of the invention. The outer rim 210 of the second side 200 also includes the plurality of apertures 202 adapted to receive connection members 204 to attach the coverplate 10 to the pump 400. Connection members 204 can include any known fasteners, such as, for example nuts and bolts as shown, or any other appropriate fastener.

The second side 200 of the coverplate 10 can also include a plurality of partial apertures that do not go through the first side 100 of the coverplate. The plurality of partial apertures can be can be, for example, polygon shaped and can further be radially spaced. According to an embodiment of the invention, the plurality of partial apertures reduce the weight of the coverplate.

FIG. 1 also illustrates a cross section of the integral flange 402. The base of the flange 412, according to the an embodiment of the invention, is tapered as illustrated by the angle 102, for example, illustrated in FIG. 1. The outside diameter of the flange 402 can also taper such that it decreases gradually as the flange extends away from the base 412 of the flange 402. For example, the outside diameter 126 of the flange at an outer end 413, according to an example embodiment, can be smaller than the outside diameter 127 at the base 412 of the flange 402.

The flange 402 circumferentially surrounds at least part of the orifice 122 so that materials (e.g., solids and fluid) are pumped through the piping, through the flange 402 of the second side and into the pump intake 404 and impeller 406 of the pump and eventually out the pump outtake 410.

Embodiments of the coverplate may further include a flow straightening vane that is cast into the inside diameter of the coverplate and is adapted to significantly reduce pre-rotation at the entrance of the pump. The straightening vane may also be positioned within the orifice of the coverplate. According to certain embodiments, the straightening vane is cast from the same material as the coverplate 10 and is shaped in a substantially straight line. The straightening vane can be solid and have a relative small thickness and width. The straightening vane according to embodiments of the present invention further stabilizes laminar flow to the pump entrance and thereby reduces the occurrence of erosion to the impeller.

Embodiments of the invention also include a method of attaching a coverplate 10 to a centrifugal pump 10 and operating the centrifugal pump 400 with a coverplate 10 attached thereto. Method embodiments can comprise the step of, for example, positioning the coverplate such that at least a part of a first side 100 of the coverplate is positioned within the pump 400. For example, the substantial circular face 208 on the first side may be positioned within the pump 400 and facing the impeller 406 of the pump. The substantially circular face 208 may be at least partially tapered towards the center of the coverplate.

Method embodiments can also include the step of attaching the coverplate 10 to the pump using one or more connection members 204 such as bolts. A substantially cylindrical body 128 includes, for example, a circumferential outer rim 210 on the first and second sides 100, 200. The outer rim 210 includes apertures through the first and second sides 100, 200 adapted to receive the one or more connection members 204. When the coverplate 10 is attached to the pump 400 according to an embodiment of the invention, an outer surface of the outer rim 210 on the first side 100 attaches to an outer surface of the pump 400, and the substantially cylindrical body 128 is positioned at least partially within the pump. The second side 200 of the coverplate 10, including the integral flange 402, faces outwardly from the pump 400 when attached thereto. A gasket can be placed between the coverplate 10 and the pump 400 to prevent leakage when materials such as hydrocarbons, sand, and other materials that are pumped in hydraulic fracturing, for example, flow through the orifice 122 of the coverplate and to the pump intake 404. Advantageously, embodiments of the invention eliminate the need, for example, for a separate spool piece that is used in conventional arrangements.

Method embodiments can also include the step of attaching a pipe of a fracturing blender to the flange 402 using a clamp coupling. The second side 200 of the coverplate 10 includes, for example, an integral flange 402 that extends outwardly from the pump when attached thereto. According to an embodiment of the invention, the flange 402 is circumscribed by a circumferential groove 112 that engages with the piping using the clamp coupling or other fastener means. According to an exemplary embodiment, a 14 inch clamp coupling made by Victaulic® can be used to attach a fracturing blender's pipe to the flange 402 of the coverplate. The pipe connected to the flange 402 can have an outside diameter of approximately 14 inches and schedule 80 pounds. The outside diameter 126 of the flange can also be approximately 14 inches according to this exemplary embodiment.

Method embodiments can also include, for example, mounting the pump to one or more of the following: a trailer mounted fracturing blender, a skid mounted fracturing blender, and a truck mounted fracturing blender. The coverplate can be attached to the pump before or after mounting the pump to the fracturing blender.

Method embodiments can also include the step of operating the pump 402 with the coverplate 10 and pipe attached thereto. The flange 402 of the coverplate circumferentially surrounds at least part of the orifice 122 so that materials are pumped through the piping, through the flange 402 of the second side and into the pump intake 404 and impeller 406 of the pump, and eventually out the pump outtake 410.

According to an embodiment, the orifice 122 has a tapered inner surface 120 that decreases in diameter from the first side 100 to the second side 200. For example, an inside diameter 104 of the orifice at the first side 100 can be approximately 13.386 inches, and an inside diameter 124 of the orifice at the second side 200 can be approximately 12.500 inches according to an embodiment of the invention. According to an exemplary embodiment, the diameter 124 of the orifice 122 at the second side 200 that connects to the piping is approximately the same as the inside diameter of the piping. The smooth and gradual taper of the inner surface 120 of the orifice 122 (and integral flange) enables a gradual taper into the suction entrance of the pump when the coverplate is attached to the pump. This provides a smooth and gradual curvature to promote laminar flow and so that there are no or fewer areas where solids such as sand can be trapped out of the pump's flow and mill holes into the internal components. Embodiments of the present invention reduce the occurrence of eddy currents and improves laminar flow through the pump entrance, which in turn reduces the occurrence of erosion damage and extends the life and dependability of the pump. The coverplate 10 can further include a straightening vane positioned within the orifice 122 to further improve laminar flow to the pump.

Although example dimensions have been disclosed, embodiments of the present invention include any appropriate dimensions, which can depend on the size of the pump and other factors.

In the drawings and specification, there have been disclosed embodiments of the embodiments of the present invention, and although specific terms are employed, the terms are used in a descriptive sense only and not for purposes of limitation. The embodiments of the present invention have been described in considerable detail with specific reference to these illustrated embodiments. It will be apparent, however, that various modifications and changes can be made within the spirit and scope of the embodiments of the present invention as described in the foregoing specification, and such modifications and changes are to be considered equivalents and part of this disclosure. 

That claimed is:
 1. A coverplate for centrifugal pumps comprising: a substantially cylindrical body having an outer surface with a circumferential outer rim that substantially surrounds the outer surface; a first side and a second side, the substantially cylindrical body surrounding an orifice with an at least partially tapered diameter that decreases from the first side to the second side; the first side having a substantially circular face that at least partially tapers toward the second side, the face of the first side adapted to be positioned at least partially within a centrifugal pump when the coverplate is attached to the centrifugal pump; the second side having an integral flange extending outwardly therefrom away from the first side, the flange of the second side circumscribed by a circumferential groove adapted to facilitate attachment of the coverplate to a suction pipe using a clamp coupling, the second side facing outwardly from the centrifugal pump when the coverplate is attached to the centrifugal pump; the outer rim having a plurality of apertures adapted to receive connecting members when the coverplate is attached to the centrifugal pump.
 2. The coverplate as defined in claim 1, wherein the coverplate further comprises a flow straightening vane positioned within the orifice adapted to stabilize laminar flow to the pump.
 3. The coverplate as defined in claim 1, wherein the pump is mounted on a fracturing truck.
 4. The coverplate as defined in claim 3, wherein an outside diameter of the suction pipe is approximately fourteen (14) inches and the pipe is schedule eighty (80) pounds.
 5. The coverplate as defined in claim 1, wherein the coverplate is cast from high chrome alloy.
 6. A coverplate for centrifugal pumps comprising: a substantially cylindrical body with a circumferential outer rim; a first side and a second side, the substantially cylindrical body surrounding an orifice with an at least partially tapered diameter; the first side having a substantially circular face that at least partially tapers, the face of the first side adapted to be positioned at least partially within a centrifugal pump when the coverplate is attached to the centrifugal pump; the second side having an integral flange extending outwardly therefrom away from the first side, the flange of the second side circumscribed by a circumferential groove adapted to facilitate attachment of the coverplate to a pipe using a clamp coupling, the second side facing outwardly from the centrifugal pump when the coverplate is attached to the centrifugal pump.
 7. The coverplate as defined in claim 6, wherein the substantially cylindrical body includes an outer rim having a plurality of apertures adapted to receive connecting members when the coverplate is attached to the centrifugal pump.
 8. The coverplate as defined in claim 6, wherein the coverplate further comprises a flow straightening vane positioned within the orifice adapted to stabilize laminar flow to the pump.
 9. The coverplate as defined in claim 6, wherein the pump is mounted on a fracturing truck.
 10. The coverplate as defined in claim 6, wherein an outside diameter of the pipe is approximately fourteen (14) inches and the pipe is schedule eighty (80) pounds.
 11. The coverplate as defined in claim 6, wherein the coverplate is cast from high chrome alloy.
 12. A method attaching a coverplate, the method comprising the steps of: positioning a coverplate such that at least part of a first side of the coverplate is positioned within a centrifugal pump, the first side of the coverplate having a substantially circular face that at least partially tapers, and attaching the coverplate to the centrifugal pump using one or more connection members, the coverplate comprising: a substantially cylindrical body surrounding an orifice with an at least partially tapered diameter; a second side of the coverplate having an integral flange extending outwardly therefrom away from the first side, the second side facing outwardly from the centrifugal pump.
 13. The method as defined in claim 12, wherein the substantially circular face is positioned at least partially within the centrifugal pump.
 14. The method as defined in claim 12, wherein the flange of the second side is circumscribed by a circumferential groove adapted to facilitate attachment of the coverplate to a pipe using a clamp coupling.
 15. The method as defined in claim 14, wherein the method further comprises the step of: attaching a pipe to the flange using a clamp coupling.
 16. The method as defined in claim 12, wherein the substantially cylindrical body further includes a circumferential outer rim with a plurality of apertures and the pump is attached to the outer rim of the coverplate.
 17. The method as defined in claim 12, wherein a diameter of the orifice decrease from the first side to the second side.
 18. The method as defined in claim 12, wherein the coverplate further comprises a flow straightening vane positioned within the orifice adapted to stabilize laminar flow to the pump.
 19. The method as defined in claim 15, the method further comprises the steps of: mounting the pump to a fracking truck; and operating the pump.
 20. The method as defined in claim 19, wherein the coverplate further comprises a flow straightening vane positioned within the orifice adapted to stabilize laminar flow to the pump. 